Optical coherence tomography (OCT) is a technology that allows for non-invasive micron-scale resolution imaging in living biological tissues. Recent OCT research has focused on developing instrumentation appropriate for imaging in clinical settings (e.g., in ophthalmology, dermatology and gastroenterology), on resolution improvements, real-time imaging, and on functional imaging, such as in color Doppler OCT.
Current-generation real-time OCT systems typically employ depth-priority scanning, with the axial scan implemented using a rapid-scan optical delay (RSOD) in the reference arm. The rapid axial scan is readily implemented using resonant scanners. However, the resulting sinusoidally varying delay axially distorts the resulting OCT imagines. In addition, the use of non-telecentric scan patterns is often necessitated by non-planar sample configurations (e.g., imagining the convex surface of the cornea or the concave surface of a hollow organ or tract).
One major impediment to the use of OCT for quantitative morphological imaging is image distortions that may occur due to several mechanisms, including nonlinearities in the reference or sample scan mechanisms, non-telecentric (diverging or converging) scan geometries, and the refraction of probe light in the sample. Non-contact imaging, one of the primary advantages of OCT, also leads to significant image distortions due to refraction of the probe beam at the interface between air and smooth surfaces, such as the cornea, or liquid accumulations in internal organs. Image distortions due to refraction may also occur at internal smooth tissue index boundaries, such as the cornea-aqueous interface in the eye.
Accordingly, a need exists for an improved method and system for quantitative imagine correction of OCT images, which overcome the above-referenced problems and others.